One Way of Thinking About the Structure of an Essay An Admittedly Imperfect Analogy
Think of the Thesis Statement as the Brain and Central Nervous System of the essay. It runs throughout the body. It regulates and sends commands to all other parts of the body.
Think of the Topic Sentences of Paragraphs as the Skeleton The skeleton gives structure. It protects the vital organs. The muscles are anchored to it.
These are the meat of your essay. Think of the Details, Evidence, & Quotations as the Muscles & Vital Organs. These are the meat of your essay. They give it life, Strength Movement & Grace.